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Heisenberg relation

It is easily seen from (90) that when the size of the basic wavelet Axo is large enough, the new relation turns itself into the old, usual Heisenberg relations, which is a very satisfactory result. This situation corresponds to the limiting case when the wavelet analysis transforms into the nonlocal Fourier analysis. [Pg.539]

In this last expression, as for the quantum representation //, the structure of a quasiclassical coherent state minimizing the uncertainty Heisenberg relations may be recognized. [Pg.285]

In the opposite end, in the strongly correlated domain, magnetic behavior was studied via Ising and Heisenberg-related empirical Hamiltonians, with actual results mainly semi-classical or mean-field-like. [Pg.730]

Weyl s proposal was a first step to derive the Heisenberg relations from the basic properties of projective unitary representations. He indicated how an observable H given in terms of the conjugate observable g and h could be characterized [18] by H = H(g,h), using the wave function expanded over the eigenvalues s and k ... [Pg.83]

X 10 for up to 202 mms for Re. They are all very small when compared with the tremendous velocities ( 7 x 10 mm s ) used by Moon in 1950 to detect nuclear resonance fluorescence without recoilless emission, and show dramatically that the Mossbauer technique eUminates both recoil and thermal broadening. The Heisenberg relation means that an excited state with a shorter half-life has a greater uncertainty in the y-transition energy and hence a broader resonance line. [Pg.18]

Continuing from remarks ( 62)-( 63), the following conclusion can be drawn The formula t F = h is often used for the estimation of the natural linewidth. This formula is sometimes interpreted as the time-energy equivalent of the Heisenberg relation, where r is the uncertainty (standard deviation) of the lifetime and F (FWHM) is that of the energy state. It should be stressed, however, that while r can play the assigned role (because the standard deviation is equal to the expected value in the case of the exponential distribution), the quantity F cannot be interpreted as standard deviation, since the Cauchy distribution does not have any. [Pg.440]

Going to the next level of chemical bonding the ligand-receptor L-R) or substrate-enzyme S-E) interactions are treated such way that the quantum (fluctuating) nature of the biomolecular reactions can be visualized by combining the relationship between the catalytic rate k J and temperature (7) with that between the reaction rate and the turnover number or the effective time of reaction (At) via Heisenberg relation,... [Pg.410]

Since the non-local bonding equation contains the local case it may be rearranged to the convenient form recalling a sort of adapted Heisenberg relation for chemical bonding the present discussion follows (Putz, 2009a,l) ... [Pg.417]

What we call level width is the energy directly related to the lifetime of a single hole in an electronic shell of an atom by the Heisenberg relation F x=h we can write F=h S where S is the sum of all the transition rates due to radiative. Auger and Coster-Kronig processes that cooperate to fill the hole. [Pg.205]

A classical Hamiltonian is obtained from the spectroscopic fitting Hamiltonian by a method that has come to be known as the Heisenberg correspondence [46], because it is closely related to the teclmiques used by Heisenberg in fabricating the fomi of quantum mechanics known as matrix mechanics. [Pg.68]

How to extract from E(qj,t) knowledge about momenta is treated below in Sec. III. A, where the structure of quantum mechanics, the use of operators and wavefunctions to make predictions and interpretations about experimental measurements, and the origin of uncertainty relations such as the well known Heisenberg uncertainty condition dealing with measurements of coordinates and momenta are also treated. [Pg.10]

In these Lorentzian lines, the parameter x deseribes the kinetie deeay lifetime of the moleeule. One says that the speetral lines have been lifetime or Heisenberg broadened by an amount proportional to 1/x. The latter terminology arises beeause the finite lifetime of the moleeular states ean be viewed as produeing, via the Heisenberg uneertainty relation AEAt >fe, states whose energy is "uneertain" to within an amount AE. [Pg.437]

The electromagnetic spectrum is a quantum effect and the width of a spectral feature is traceable to the Heisenberg uncertainty principle. The mechanical spectrum is a classical resonance effect and the width of a feature indicates a range of closely related r values for the model elements. [Pg.183]

Notice that in this example, the speed of the packet is inversely proportional to the packet s spatial size. While there is certainly nothing unique about this particular representation, it is interesting to speculate, along with Minsky, whether it may be true that, just as the simultaneous information about position and momentum is fundamentally constrained by Heisenberg s uncertainty relation in the physical universe, so too, in a discrete CA universe, there might be a fundamental constraint between the volume of a given packet and the amount of information that can be encoded within it. [Pg.663]

The first consistent attempt to unify quantum theory and relativity came after Schrddinger s and Heisenberg s work in 1925 and 1926 produced the rules for the quantum mechanical description of nonrelativistic systems of point particles. Mention should be made of the fact that in these developments de Broglie s hypothesis attributing wave-corpuscular properties to all matter played an important role. Central to this hypothesis are the relations between particle and wave properties E — hv and p = Ilk, which de Broglie advanced on the basis of relativistic dynamics. [Pg.484]

To facilitate the derivation we shall assume that we are in the Heisenberg picture and dealing with a time-independent hamiltonian, i.e., H(t) — 27(0) = 27, in which case Heisenberg operators at different times are related by the equation... [Pg.599]

There are now two alternate consistent ways for the observers to relate their observables and state vectors, the Heisenberg-type and the Schrodinger-type descriptions. [Pg.667]

Heisenberg representation 267 helium see nitrogen-helium system Hermite polynomials 24, 25 Hubbard dependence 8 Hubbard relation... [Pg.296]

The location and momentum of a particle are complementary that is, both the location and the momentum cannot be known simultaneously with arbitrary precision. The quantitative relation between the precision of each measurement is described by the Heisenberg uncertainty principle. [Pg.140]

In recent years the old quantum theory, associated principally with the names of Bohr and Sommerfeld, encountered a large number of difficulties, all of which vanished before the new quantum mechanics of Heisenberg. Because of its abstruse and difficultly interpretable mathematical foundation, Heisenberg s quantum mechanics cannot be easily applied to the relatively complicated problems of the structures and properties of many-electron atoms and of molecules in particular is this true for chemical problems, which usually do not permit simple dynamical formulation in terms of nuclei and electrons, but instead require to be treated with the aid of atomic and molecular models. Accordingly, it is especially gratifying that Schrodinger s interpretation of his wave mechanics3 provides a simple and satisfactory atomic model, more closely related to the chemist s atom than to that of the old quantum theory. [Pg.256]

The energy q of a nuclear or electronic excited state of mean lifetime t cannot be determined exactly because of the limited time interval At available for the measurement. Instead, q can only be established with an inherent uncertainty, AE, which is given by the Heisenberg uncertainty relation in the form of the conjugate variables energy and time,... [Pg.9]

The Heisenberg uncertainty principle is a consequence of the stipulation that a quantum particle is a wave packet. The mathematical construction of a wave packet from plane waves of varying wave numbers dictates the relation (1.44). It is not the situation that while the position and the momentum of the particle are well-defined, they cannot be measured simultaneously to any desired degree of accuracy. The position and momentum are, in fact, not simultaneously precisely defined. The more precisely one is defined, the less precisely is the other, in accordance with equation (1.44). This situation is in contrast to classical-mechanical behavior, where both the position and the momentum can, in principle, be specified simultaneously as precisely as one wishes. [Pg.22]

Another Heisenberg uncertainty relation exists for the energy E ofa particle and the time t at which the particle has that value for the energy. The uncertainty Am in the angular frequency of the wave packet is related to the uncertainty A in the energy of the particle by Am = h.E/h, so that the relation (1.25) when applied to a free particle becomes... [Pg.22]

Combining equations (1.46) and (1.47), we see that AEAt = AxAp. Thus, the relation (1.45) follows from (1.44). The Heisenberg uncertainty relation (1.45) is treated more thoroughly in Section 3.10. [Pg.23]

This general expression relates the uncertainties in the simultaneous measurements of A and B to the commutator of the corresponding operators A and B and is a general statement of the Heisenberg uncertainty principle. [Pg.101]

Using the results of Section 4.4, we may easily verify for the harmonic oscillator the Heisenberg uncertainty relation as discussed in Section 3.11. Specifically, we wish to show for the harmonic oscillator that... [Pg.125]

The original Hohenberg-Kohn theorem was directly applicable to complete systems [14], The first adaptation of the Hohenberg-Kohn theorem to a part of a system involved special conditions the subsystem considered was a part of a finite and bounded entity regarded as a hypothetical system [21], The boundedness condition, in fact, the presence of a boundary beyond which the hypothetical system did not extend, was a feature not fully compatible with quantum mechanics, where no such boundaries can exist for any system of electron density, such as a molecular electron density. As a consequence of the Heisenberg uncertainty relation, molecular electron densities cannot have boundaries, and in a rigorous sense, no finite volume, however large, can contain a complete molecule. [Pg.67]


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See also in sourсe #XX -- [ Pg.50 ]




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